CANANDAIGUA, N.Y. — The collision was as common as any in racing. Kevin Ward Jr.’s car spun twice like a top, wheels hugging the wall, before it plopped backward on the dimly lit dirt track.

In a sport steeped with bravado, what happened next was another familiar, but treacherous, move: Wearing a black firesuit and black helmet, the 20-year-old Ward unbuckled himself, climbed out of the winged car into the night and defiantly walked onto the track at Canandaigua Motorsports Park.

He gestured, making his disgust evident with the driver who triggered the wreck with a bump: three-time NASCAR champion Tony Stewart.

Ward, a relative unknown compared with NASCAR’s noted swashbuckler, was nearly hit by another passing car as he pointed with his right arm in Stewart’s direction. As he confronted Stewart in his passing car, disaster struck.

Ward was standing to the right of Stewart’s familiar No. 14 car, which seemed to fishtail from the rear and hit him. According to video and witness accounts, Ward was killed when he was sucked underneath the car and hurtled through the air before landing on his back as fans looked on in horror.

Authorities questioned Stewart, 43, once on Saturday night and went to Watkins Glen to talk to him again Sunday. They described him as ‘‘visibly shaken’’ after the crash and said he was cooperative.

Stewart dropped out of Sunday’s NASCAR race at Watkins Glen.

‘‘There aren’t words to describe the sadness I feel about the accident that took the life of Kevin Ward Jr.,’’ Stewart said in a statement.

On Sunday, Ontario County Sheriff Philip Povero said investigators also don’t have any evidence at this point in the investigation to support criminal intent. But he also said that criminal charges have not been ruled out.

David S. Weinsten, a former state and federal prosecutor in Miami who is now in private practice, said it would be difficult to prove criminal intent.

‘‘I think even with the video, it’s going to be tough to prove that this was more than just an accident and that it was even culpable negligence, which he should've known or should've believed that by getting close to this guy, that it was going to cause the accident,’’ he said.

The sheriff renewed a plea for spectators to turn over photos and videos of the crash. Investigators were reconstructing the accident and looking into everything from the dim lighting on a portion of the track to how muddy it was, as well as if Ward’s dark firesuit played a role in his death, given the conditions.

‘‘I've seen it many times in NASCAR,” witness Michael Messerly said, “where a driver will confront the other one, and a lot of times they'll try to speed past them. And that’s what it appeared to me as if what Tony Stewart did, he tried to speed past Ward. And the next thing I could see, I didn’t see Ward any more. It just seemed like he was suddenly gone.’’

Driver Cory Sparks, a friend of Ward's, was a few cars back when Ward was killed.

‘‘The timing was unsafe,’’ he said of Ward’s decision to get out of his car to confront Stewart. ‘‘When your adrenaline is going, and you’re taken out of a race, your emotions flare.’’

It’s often just a part of racing. Drivers from Jeff Gordon to Danica Patrick have erupted in anger on the track at another driver. The confrontations are part of the sport’s allure: Fans love it and cheer wildly from the stands.

Throughout his career, Stewart has been no stranger to on-track altercations that occasionally spilled onto pit road or into interviews. He punched a photographer in 2002, drawing a $50,000 fine. Stewart called out drivers, reporters, and even fans, and sometimes his temper boiled over — Stewart occasionally has had to be restrained by members of his crew.

‘‘I'll tell you, I don’t know what’s wrong with that boy,’’ analyst and former driver Darrell Waltrip said, leading Stewart to insult Waltrip during a post-race interview.

Stewart, whose reputation for being a hothead earned him the nickname ‘‘Smoke,’’ once wound up like a pitcher and tossed his helmet like a fastball at Matt Kenseth’s windshield.

Last year after a Sprint Cup event, Stewart followed Joey Logano to pit road, threw punches and had to be restrained.

‘‘I don’t enjoy getting mad like that,’’ he told reporters after the dust-up with Logano.

The crash also raised questions about whether Stewart will continue with his hobby of racing on small tracks on the side of the big-money NASCAR races. He has long defended his participation in racing on tracks like the one where the crash happened, even as accidents and injury have put his day job in NASCAR at risk.

Saturday’s crash came almost exactly a year after Stewart suffered a compound fracture to his right leg in a sprint car race in Iowa. The injury cost him the second half of the NASCAR season and sidelined him during NASCAR’s Chase for the Sprint Cup Championship. Stewart only returned to sprint track racing last month.

The crash site is the same track where Stewart was involved in a July 2013 accident that seriously injured a 19-year-old driver. He later took responsibility for his car making contact with another and triggering the 15-car accident that left Alysha Ruggles with a compression fracture in her back.

‘‘Everybody has hobbies,’’ he said last month, adding that ‘‘there are a lot of other things I could be doing that are a lot more dangerous and a lot bigger waste of time with my time off do than doing that.’’

Ward’s family said it ‘‘appreciates all the prayer and support’’ but that members ‘‘would like time to grieve.’’

Greg Zipadelli, competition director for Stewart-Haas Racing, said Stewart felt strongly he should not race after the wreck. Regan Smith replaced him in his car for the Cheez-It 355.

Jenna Fryer, John Kekis, and David Klepper of the Associated Press contributed to this report.